Gilead Sciences, Inc. (Nasdaq: GILD) announced today its results of
operations for the fourth quarter and full year 2017. Total revenues for
the fourth quarter of 2017 were $5.9 billion compared to $7.3 billion
for the same period in 2016. Net loss for the fourth quarter of 2017 was
$3.9 billion, or $2.96 loss per share, compared to net income of $3.1
billion, or $2.34 per diluted share for the same period in 2016. The net
loss for the fourth quarter includes an estimated $5.5 billion charge
related to the enactment of the Tax Cuts and Jobs Act (Tax Reform)(1).
Non-GAAP net income for the fourth quarter of 2017 was $2.3 billion, or
$1.78 per diluted share, compared to $3.6 billion, or $2.70 per diluted
share for the same period in 2016. Non-GAAP net income excludes amounts
related to acquisition-related, up-front collaboration, stock-based
compensation and other expenses, and the impact of Tax Reform.

Full year 2017 total revenues were $26.1 billion, compared to $30.4
billion for 2016. Net income for 2017 was $4.6 billion, or $3.51 per
diluted share, compared to $13.5 billion, or $9.94 per diluted share for
2016. Non-GAAP net income for 2017 was $11.7 billion, or $8.84 per
diluted share, compared to $15.7 billion, or $11.57 per diluted share
for 2016.

Three Months Ended

Twelve Months Ended

December 31,

December 31,

(In millions, except per share amounts)

2017

2016

2017

2016

Product sales

$

5,837

$

7,216

$

25,662

$

29,953

Royalty, contract and other revenues

112

104

445

437

Total revenues

$

5,949

$

7,320

$

26,107

$

30,390

Net income (loss) attributable to Gilead

$

(3,865

)

$

3,108

$

4,628

$

13,501

Non-GAAP net income*

$

2,343

$

3,585

$

11,654

$

15,713

Diluted earnings / (loss) per share**

$

(2.96

)

$

2.34

$

3.51

$

9.94

Non-GAAP diluted earnings per share*

$

1.78

$

2.70

$

8.84

$

11.57

*

Non-GAAP net income and non-GAAP diluted earnings per share
exclude acquisition-related, up-front collaboration, stock-based
compensation and other expenses, and the impact of Tax Reform. A
reconciliation between GAAP and non-GAAP financial information is
provided in the tables on pages 8, 9 and 10.

**

Shares used in loss per share calculation for the three months
ended December 31, 2017 exclude 13 million shares from dilutive
equity awards.

___________________________________

(1) Refer to page 3 for details.

Product Sales

Total product sales for the fourth quarter of 2017 were $5.8 billion,
compared to $7.2 billion for the same period in 2016. Product sales for
the fourth quarter of 2017 were $4.1 billion in the United States, $1.1
billion in Europe and $553 million in other locations. Product sales for
the fourth quarter of 2016 were $4.9 billion in the United States, $1.4
billion in Europe and $870 million in other locations.

Total product sales during 2017 were $25.7 billion, compared to $30.0
billion in 2016. For 2017, product sales were $18.1 billion in the
United States, $5.0 billion in Europe and $2.6 billion in other
locations. For 2016, product sales were $19.3 billion in the United
States, $6.1 billion in Europe and $4.6 billion in other locations.

Antiviral Product Sales

Antiviral product sales, which include sales of our HIV, chronic
hepatitis B (HBV) and chronic hepatitis C (HCV) products, were $5.2
billion for the fourth quarter of 2017 compared to $6.6 billion for the
same period in 2016. For 2017, antiviral product sales were $23.3
billion compared to $27.7 billion in 2016.

HIV and HBV product sales for the fourth quarter of 2017 were $3.7
billion compared to $3.4 billion for the same period in 2016 and $14.2
billion for the full year 2017 compared to $12.9 billion in 2016. The
increases were primarily driven by the continued uptake of our
tenofovir alafenamide (TAF)-based products, Genvoya®
(elvitegravir 150 mg/cobicistat 150 mg/emtricitabine 200 mg/tenofovir
alafenamide 10 mg), Descovy® (emtricitabine 200
mg/tenofovir alafenamide 25 mg) and Odefsey® (emtricitabine
200 mg/rilpivirine 25 mg/tenofovir alafenamide 25 mg).

HCV product sales, which consist of Harvoni® (ledipasvir 90
mg/sofosbuvir 400 mg), Sovaldi® (sofosbuvir 400 mg), Epclusa®
(sofosbuvir 400 mg/velpatasvir 100 mg) and Vosevi®
(sofosbuvir 400 mg/velpatasvir 100 mg/voxilaprevir 100 mg), were $1.5
billion for the fourth quarter of 2017 compared to $3.2 billion for
the same period in 2016 and $9.1 billion for the full year 2017
compared to $14.8 billion in 2016. The declines were across all major
markets.

Other Product Sales

Other product sales, which include Letairis® (ambrisentan),
Ranexa® (ranolazine) and AmBisome® (amphotericin B
for liposome injection), were $624 million for the fourth quarter of
2017 compared to $621 million for the same period in 2016. For 2017,
other product sales were $2.3 billion compared to $2.2 billion in 2016.

Operating Expenses

Three Months Ended

Twelve Months Ended

December 31,

December 31,

(In millions)

2017

2016

2017

2016

Research and development (R&D) expenses

$

1,150

$

1,208

$

3,734

$

5,098

Non-GAAP R&D expenses*

$

845

$

959

$

3,291

$

3,749

Selling, general and administrative (SG&A) expenses

$

1,252

$

992

$

3,878

$

3,398

Non-GAAP SG&A expenses*

$

923

$

938

$

3,363

$

3,194

*

Non-GAAP R&D and SG&A expenses exclude acquisition-related,
up-front collaboration, stock-based compensation and other
expenses. A reconciliation between GAAP and non-GAAP financial
information is provided in the tables on pages 8, 9 and 10.

During the fourth quarter of 2017, compared to the same period in 2016:

Provision for income taxes was $6.0 billion for the fourth quarter of
2017 compared to $821 million for the same period in 2016 and $8.9
billion for the full year 2017 compared to $3.6 billion in 2016. The
increases were primarily due to an estimated charge of $5.5 billion from
Tax Reform, which was enacted on December 22, 2017 and lowers U.S.
corporate income tax rates as of January 1, 2018, implements a
territorial tax system and imposes a repatriation tax on deemed
repatriated earnings of foreign subsidiaries. This estimate is
provisional and based on our initial analysis and current
interpretation. Given the complexity of the legislation, anticipated
guidance from the U.S. Treasury, and the potential for additional
guidance from the Securities and Exchange Commission (“SEC”) or the
Financial Accounting Standards Board, this estimate may be adjusted
during 2018.

Non-GAAP provision for income taxes excludes the estimated charge of
$5.5 billion from Tax Reform. A reconciliation between GAAP and non-GAAP
financial information is provided in the tables on pages 8, 9 and 10.

Cash, Cash Equivalents and Marketable Securities

As of December 31, 2017, Gilead had $36.7 billion of cash, cash
equivalents and marketable securities compared to $32.4 billion as of
December 31, 2016. During 2017, Gilead generated $11.9 billion in
operating cash flow and in connection with the acquisition of Kite,
Gilead issued $3.0 billion aggregate principal amount of senior
unsecured notes and $6.0 billion aggregate principal amount of term loan
facilities, of which $1.5 billion was repaid in December 2017.
Additionally, Gilead paid cash dividends of $2.7 billion and utilized
$954 million on stock repurchases.

Non-GAAP Product Gross Margin, R&D and SG&A expenses and
effective tax rate exclude acquisition-related, up-front
collaboration, stock-based compensation and other expenses, and
changes to our estimates relating to Tax Reform during 2018. A
reconciliation between GAAP and non-GAAP full year 2018 guidance
is provided in the tables on page 11.

Corporate Highlights

Announced that Executive Chairman John C. Martin, PhD will transition
from his current role of Executive Chairman to Chairman of the Board
of Directors effective March 9, 2018.

Announced the acquisition of Cell Design Labs, gaining new technology
platforms that will enhance research and development efforts in
cellular therapy.

Announced the launch of the Gilead COMPASS (COMmitment to Partnership
in Addressing HIV/AIDS in Southern States)
Initiative, a 10-year, $100 million commitment to support
organizations working to address the HIV/AIDS epidemic in the Southern
United States.

Announced the promotion of Alessandro Riva, MD, to Executive Vice
President, Oncology Therapeutics, with responsibility for Gilead’s
hematology and oncology programs, including cell therapy research and
development.

Product & Pipeline Updates announced by Gilead
during the Fourth Quarter of 2017 include:

HIV and Liver Diseases Programs

Presented data at The Liver Meeting® 2017 which included
the announcement of:

Results from a Phase 2, randomized, placebo-controlled trial
evaluating two doses of GS-0976, an oral, investigational
inhibitor of Acetyl-CoA carboxylase, in patients with nonalcoholic
steatohepatitis (NASH). The data demonstrate that the higher dose
of GS-0976 (20 mg taken orally once daily) when administered for
12 weeks was associated with statistically significant reductions
in hepatic steatosis (buildup of fat in the liver) and a
noninvasive marker of fibrosis compared to placebo.

Announced detailed 48-week results from a Phase 3 study evaluating the
efficacy and safety of switching virologically suppressed HIV-1
infected adult patients from a multi-tablet regimen containing a
boosted protease inhibitor (bPI) to a fixed-dose combination of
bictegravir (50 mg) (BIC), a novel investigational integrase strand
transfer inhibitor, and emtricitabine/tenofovir alafenamide (200/25
mg) (FTC/TAF), a dual-NRTI backbone. In the ongoing study, BIC/FTC/TAF
was found to be statistically non-inferior to regimens containing bPIs
and demonstrated no treatment-emergent resistance at 48 weeks. The
data were presented at IDWeek 2017.

Announced a new licensing agreement with the Medicines Patent Pool
(MPP), a United Nations-backed public health organization, to expand
access to BIC upon regulatory approval in the United States. Through
this agreement, MPP can sub-license rights to BIC to generic drug
companies in India, China and South Africa to manufacture therapies
containing BIC for distribution in 116 low- and middle-income
countries.

Oncology and Cell Therapy Programs

Announced updated results from the ongoing Phase 1/2 ZUMA-3 study of
KTE-C19, a CD19 chimeric antigen receptor T (CAR T) cell therapy,
which is investigational, for the treatment of adult patients with
relapsed or refractory acute lymphoblastic leukemia (ALL). With a
minimum of eight weeks of follow-up, 71 percent of ALL patients
(n=17/24) who received a single infusion of KTE-C19 achieved complete
tumor remission (complete remission (CR) or CR with incomplete
hematological recovery). The ZUMA-3 study results were presented in an
oral session at the Annual Meeting of the American Society of
Hematology.

Announced long-term follow-up data from the ZUMA-1 study of Yescarta™
(axicabtagene ciloleucel) in patients with refractory large B-cell
lymphoma. With a minimum follow-up of one year after a single infusion
of Yescarta (median follow-up of 15.4 months), 42 percent of patients
continued to respond to therapy, including 40 percent with a complete
remission. Detailed results from this updated analysis were
simultaneously presented at the Annual Meeting of the American Society
of Hematology, and published in The New England Journal of Medicine.

Announced that U.S. Food and Drug Administration has granted regular
approval to Yescarta, the first CAR T cell therapy for the treatment
of adult patients with relapsed or refractory large B-cell lymphoma
after two or more lines of systemic therapy, including diffuse large
B-cell lymphoma (DLBCL) not otherwise specified, primary mediastinal
large B-cell lymphoma, high-grade B-cell lymphoma, and DLBCL arising
from follicular lymphoma (transformed follicular lymphoma).

Non-GAAP Financial Information

The information presented in this document has been prepared by Gilead
in accordance with U.S. generally accepted accounting principles (GAAP),
unless otherwise noted as non-GAAP. Management believes non-GAAP
information is useful for investors, when considered in conjunction with
Gilead’s GAAP financial information, because management uses such
information internally for its operating, budgeting and financial
planning purposes. Non-GAAP information is not prepared under a
comprehensive set of accounting rules and should only be used to
supplement an understanding of Gilead’s operating results as reported
under GAAP. Non-GAAP measures may be defined and calculated differently
by other companies in the same industry. A reconciliation between GAAP
and non-GAAP financial information is provided in the tables on pages 8,
9, 10 and 11.

Conference Call

At 4:30 p.m. Eastern Time today, Gilead’s management will host a
conference call and a simultaneous webcast to discuss results from its
fourth quarter 2017 and full year 2017 as well as provide 2018 guidance
and a general business update. To access the webcast live via the
internet, please connect to the company’s website at www.gilead.com/investors
15 minutes prior to the conference call to ensure adequate time for any
software download that may be needed to hear the webcast. Alternatively,
please call (877) 359-9508 (U.S.) or (224) 357-2393 (international) and
dial the conference ID 6478317 to access the call.

A replay of the webcast will be archived on the company’s website for
one year, and a phone replay will be available approximately two hours
following the call through February 8, 2018. To access the phone replay,
please call (855) 859-2056 (U.S.) or (404) 537-3406 (international) and
dial the conference ID 6478317.

About Gilead

Gilead Sciences is a biopharmaceutical company that discovers, develops
and commercializes innovative therapeutics in areas of unmet medical
need. The company’s mission is to advance the care of patients suffering
from life-threatening diseases. Gilead has operations in more than 35
countries worldwide, with headquarters in Foster City, California.

Forward-looking Statements

Statements included in this press release that are not historical in
nature are forward-looking statements within the meaning of the Private
Securities Litigation Reform Act of 1995. Gilead cautions readers that
forward-looking statements are subject to certain risks and
uncertainties that could cause actual results to differ materially.
These risks and uncertainties include: Gilead’s ability to achieve its
anticipated full year 2018 financial results; Gilead’s ability to
sustain growth in revenues for its antiviral and other programs; the
risk that private and public payers may be reluctant to provide, or
continue to provide, coverage or reimbursement for new products,
including Vosevi, Yescarta, Epclusa, Harvoni, Genvoya, Odefsey, Descovy
and Vemlidy; austerity measures in European countries that may increase
the amount of discount required on Gilead’s products; an increase in
discounts, chargebacks and rebates due to ongoing contracts and future
negotiations with commercial and government payers; a larger than
anticipated shift in payer mix to more highly discounted payer segments
and geographic regions and decreases in treatment duration; availability
of funding for state AIDS Drug Assistance Programs (ADAPs); continued
fluctuations in ADAP purchases driven by federal and state grant cycles
which may not mirror patient demand and may cause fluctuations in
Gilead’s earnings; market share and price erosion caused by the
introduction of generic versions of Viread and Truvada outside the
United States, an uncertain global macroeconomic environment; and
potential amendments to the Affordable Care Act or other government
action that could have the effect of lowering prices or reducing the
number of insured patients; the possibility of unfavorable results from
clinical trials involving investigational compounds; Gilead’s ability to
initiate clinical trials in its currently anticipated timeframes; the
levels of inventory held by wholesalers and retailers which may cause
fluctuations in Gilead’s earnings; Gilead’s ability to submit new drug
applications for new product candidates in the timelines currently
anticipated; Gilead’s ability to receive regulatory approvals in a
timely manner or at all, for new and current products, including
BIC/FTC/TAF; Gilead’s ability to successfully commercialize its
products, including Vosevi, Yescarta, Epclusa, Harvoni, Genvoya,
Odefsey, Descovy and Vemlidy; the risk that physicians and patients may
not see advantages of these products over other therapies and may
therefore be reluctant to prescribe the products; Gilead’s ability to
successfully develop its hematology/oncology and
inflammation/respiratory programs; safety and efficacy data from
clinical studies may not warrant further development of Gilead’s product
candidates, including GS-0976 and KTE-C19; Gilead’s ability to pay
dividends or complete its share repurchase program due to changes in its
stock price, corporate or other market conditions; fluctuations in the
foreign exchange rate of the U.S. dollar that may cause an unfavorable
foreign currency exchange impact on Gilead’s future revenues and pre-tax
earnings; and other risks identified from time to time in Gilead’s
reports filed with the SEC. In addition, Gilead makes estimates and
judgments that affect the reported amounts of assets, liabilities,
revenues and expenses and related disclosures. Gilead bases its
estimates on historical experience and on various other market specific
and other relevant assumptions that it believes to be reasonable under
the circumstances, the results of which form the basis for making
judgments about the carrying values of assets and liabilities that are
not readily apparent from other sources. Actual results may differ
significantly from these estimates. You are urged to consider statements
that include the words may, will, would, could, should, might, believes,
estimates, projects, potential, expects, plans, anticipates, intends,
continues, forecast, designed, goal, or the negative of those words or
other comparable words to be uncertain and forward-looking. Gilead
directs readers to its press releases, Quarterly Report on Form 10-Q for
the quarter ended September 30, 2017 and other subsequent disclosure
documents filed with the SEC. Gilead claims the protection of the Safe
Harbor contained in the Private Securities Litigation Reform Act of 1995
for forward-looking statements.

All forward-looking statements are based on information currently
available to Gilead, and Gilead assumes no obligation to update any such
forward-looking statements.

ATRIPLA® is a registered trademark of Gilead Sciences, LLC.
LEXISCAN® is a registered trademark of Astellas U.S. LLC.
MACUGEN® is a registered trademark of Eyetech, Inc. TAMIFLU®
is a registered trademark of Hoffmann-La Roche Inc.

For more information on Gilead Sciences, Inc., please visit www.gilead.com
or call the Gilead Public Affairs Department at 1-800-GILEAD-5
(1-800-445-3235).

GILEAD SCIENCES, INC.

CONDENSED CONSOLIDATED STATEMENTS OF INCOME

(unaudited)

(in millions, except per share amounts)

Three Months Ended

Twelve Months Ended

December 31,

December 31,

2017

2016

2017

2016

Revenues:

Product sales

$

5,837

$

7,216

$

25,662

$

29,953

Royalty, contract and other revenues

112

104

445

437

Total revenues

5,949

7,320

26,107

30,390

Costs and expenses:

Cost of goods sold

1,256

1,075

4,371

4,261

Research and development expenses

1,150

1,208

3,734

5,098

Selling, general and administrative expenses

1,252

992

3,878

3,398

Total costs and expenses

3,658

3,275

11,983

12,757

Income from operations

2,291

4,045

14,124

17,633

Interest expense

(297

)

(265

)

(1,118

)

(964

)

Other income (expense), net

132

140

523

428

Income before provision for income taxes

2,126

3,920

13,529

17,097

Provision for income taxes

5,962

821

8,885

3,609

Net income (loss)

(3,836

)

3,099

4,644

13,488

Net income (loss) attributable to noncontrolling interest

29

(9

)

16

(13

)

Net income (loss) attributable to Gilead

$

(3,865

)

$

3,108

$

4,628

$

13,501

Net income (loss) per share attributable to Gilead common
stockholders - basic

$

(2.96

)

$

2.36

$

3.54

$

10.08

Shares used in per share calculation - basic

1,307

1,316

1,307

1,339

Net income (loss) per share attributable to Gilead common
stockholders - diluted

Income tax effect related to stock-based compensation expenses for
the three and twelve months ended December 31, 2017 includes the
incremental tax benefit of $31 million and $91 million,
respectively, recognized from the adoption of Accounting Standards
Update 2016-09 “Improvements to Employee Share-Based Payment
Accounting”

(4)

Shares used in loss per share calculation for the three months ended
December 31, 2017 exclude 13 million shares from dilutive equity
awards

(5)

Amounts for the three and twelve months ended December 31, 2017
include an estimated charge of $5.8 billion relating to the deemed
repatriation of unremitted earnings of foreign subsidiaries and an
estimated benefit of $308 million relating to the re-measurement of
deferred taxes

(6)

Amounts may not sum due to rounding

GILEAD SCIENCES, INC.

RECONCILIATION OF GAAP TO NON-GAAP 2018 FULL YEAR GUIDANCE

(unaudited)

(in millions, except percentages and per share amounts)

ProvidedFebruary 6, 2018

Projected product gross margin GAAP to non-GAAP reconciliation:

GAAP projected product gross margin

78% - 80%

Acquisition-related expenses

7% - 7%

Non-GAAP projected product gross margin(1)

85% - 87%

Projected research and development expenses GAAP to non-GAAP
reconciliation:

GAAP projected research and development expenses

$3,785 - $4,050

Stock-based compensation expenses(2)

(315) - (350)

Acquisition-related expenses / up-front collaboration expenses

(70) - (100)

Non-GAAP projected research and development expenses

$3,400 - $3,600

Projected selling, general and administrative expenses GAAP to
non-GAAP reconciliation: